BSA Owners' Club Workshop Discussions

The BSA Workshop => Singles => Topic started by: TIGER on 25 Aug, 2018, 19:53

Title: C15 stopping
Post by: TIGER on 25 Aug, 2018, 19:53
Hi
Because of the fine weather I have ridden much more than usual.
However the stopping power of the front brake is very weak.
Any ideas how this can be improved?
Regards
           Tim
Title: Re: C15 stopping
Post by: ducati2242 on 26 Aug, 2018, 07:36
You can purchase a longer brake arm which will increase the % of pressure but only by 10% or so . I'd look at your brake linings to see if they are glazed or particularly hard . https://classicbikepartsuk.uk/product/bsa-c15-b40-40-5530-h18-extended-front-brake-arm-lever/
Title: Re: C15 stopping
Post by: paulm on 26 Aug, 2018, 10:41
Unfortionatley the only person who could ever make brakes work Alan Cambell of clasic brake services has now retired and no one can come close to him, i have fitted a twin leader to mine
Title: Re: C15 stopping
Post by: TIGER on 26 Aug, 2018, 10:52
Thanks for both replies.
I would be very interested in the method/parts of fitting the twin leading shoes.
Is you bike a C15 ?
Title: Re: C15 stopping
Post by: MICKREEVES on 31 Aug, 2018, 08:21
I made a twin leading shoe brake.
I fitted and extra cam in place of the pivot pin.
Cut the cams down to single sided. I never tried it out!
I think I put details on this site.
Mick
Title: Re: C15 stopping
Post by: Dean Southall on 31 Aug, 2018, 09:02
I'm trying Slimmers World ;)
Title: Re: C15 stopping
Post by: AdrianS on 31 Aug, 2018, 10:51
I found the best way to improve the braking of my B40 and Bantam was to stick some car brake pads to the soles of my shoes!!

No really, the front brakes aren't that good. The rear brakes are a lot better but the front brake is the most important one for weight transfer to the front wheel for stopping. When I took my Bantam for an mot after a rebuild a few years ago I said to the tester I had no confidence in the front brake. We put it on the rolling brake tester and the figure it gave out was at least 50% better than the minimum figure needed to pass! Just shows how poor the brakes can be to gain a pass.
The longer brake lever will help to increase the force you can transfer to the brake shoes but does make the lever travel a little longer.
Title: Re: C15 stopping
Post by: MICKREEVES on 31 Aug, 2018, 13:09
There is another possible way to improve the stopping power of your brake.
Many riders (OR Drivers) never apply their brakes more than gently.   
The linings may not be fully bedded in or may have a 'glazed' surface.
Try repeated hard applications of the brake, at high speed.
This can often be effective, making a more powerful brake.
Mick
Title: Re: C15 stopping
Post by: MICKREEVES on 31 Aug, 2018, 16:01
My C15 front brake will sqeal on the road with hard application. Good enough!
Mick
Title: Re: C15 stopping
Post by: TIGER on 31 Aug, 2018, 23:06
Thanks Gents.
Anyone know of hand levers which give more advantage.
Title: Re: C15 stopping
Post by: AdrianS on 01 Sep, 2018, 08:44
I don't think there are any hand levers that will help. The only lever I have seen is the longer one on the brake cam pivot which is claimed to give 8-10% more power.
Title: Re: C15 stopping
Post by: JulianS on 01 Sep, 2018, 09:40
The handlebar levers were made with nipple to pivot dimensions of 7/8 inch and 1 1/16 inch.

The levers used on BSA were usually 7/8 inch. Substituting 1 1/16 lever has the effect of reducing the movement at the hub lever for a given movement of the bar lever at the expense of heavier action.

Whether a change of lever would improve brake power I do not know.

You may be able to improve the stopping power by trying different lining material. Originally Ferodo listed 2 different materials for C15 linings, MS3 a moulded one and MZ41 and woven one with a bit more bite. Try one of those businesses who reline your own shoes and tell them what you want and they may be able to supply a similar modern non asbestos material rather than buying a set new shoes with annonymous linings.

You also need to check the braking surface of the drum, the fit of the cam in brake plate etc and the cable.
Title: Re: C15 stopping
Post by: TIGER on 01 Sep, 2018, 11:20
Many thanks Julian.
Going to try and find some 11/16 centre.
Regards
           Tim
Title: Re: C15 stopping
Post by: JulianS on 01 Sep, 2018, 13:15
Sorry should read "increasing movement at the hub lever............"
Title: Re: C15 stopping
Post by: MICKREEVES on 02 Sep, 2018, 07:29
Have you TRIED the idea of bedding in the brake, by very hard use? Always stop with full power on the front brake, Try HARD application when riding.
mick
Title: Re: C15 stopping
Post by: Dean Southall on 02 Sep, 2018, 09:55
Remove wheel and then brake plate.
Rub a stick of chalk over the shoes.
Replace brake plate and spin wheel then apply brake.
Remove brake plate and look for high spots on shoes.
File or belt sand high spots and re-test.
Repeat until not high spots.
Title: Re: C15 stopping
Post by: paulm on 02 Sep, 2018, 20:56
mine is a c15 with a starfire brake fitted
Title: Re: C15 stopping
Post by: MICKREEVES on 05 Sep, 2018, 17:12
I fitted my twin leading shoe brake to the bike. The whell was a bit stiff to turn.
I rode it down the garden with the brake on, It freed up. The brake had very little power.
After a few circuits, the power was enough to go, warily, on the road.
I did one mile on a side road, applying the brake steadily, off and on. The brake improved.
After the mile, the brake was quit reasonable, not as good as my original standard brake, but i will leave it on
for further bedding in.
I did have to alter the brake cable, removing about two inches of outer cable.
Mic photo attached
Title: Re: C15 stopping
Post by: MICKREEVES on 24 Sep, 2018, 13:27
My C15 front brake will sqeal on the road with hard application. Good enough!
Mick
What I meant was Skid  on the road, that is locked front wheel. More than enough power.
Mick
Title: Re: C15 stopping
Post by: MICKREEVES on 06 Oct, 2018, 07:36
See new thread '190 stopping'
Mick